A compacting machine can take the form of a vibrating compactor. Vibrating compactors are dynamic compacting machines that are adapted to transfer energy, in addition to their own weight, into a volume to be compacted, for example, the ground. For this purpose, use is usually made of vibration produced by unbalanced masses. Vibrating compactors can be used, for example, for the purpose of compacting the subsurface of roads, runways, or dams. They take the form of, for example, agitator plates, vibrating rollers, single-drum compactors, vibratory plates, duplex rollers, or trench compactors. They can be used in the construction of roads and paths and wherever the ground or pavings have to be compacted. By this means, it is possible to improve the load bearing strength of a subsurface and to reduce subsidence.
Such vibrating compactors have at least one drum or plate, to which the vibration produced by the unbalanced mass can be transferred. The unbalanced mass is usually provided on a shaft, as, for example, an imbalance shaft mounted on roller bearings. In some cases, a plurality of adjustable unbalanced masses is provided so that various types of vibration can be produced.
Known vibration generators comprising an unbalanced mass or a plurality of unbalanced masses take up much room. The construction, thereof, is complicated and expensive. In operation, the degree of noise generated is high and a limit has been reached as regards the permissible stresses, more particularly, the centrifugal forces and rotational speeds.